Here’s a problem you veteran hand planers may know how to stop.
In a few minutes, I’ve gone from the elation and pride of honing and polishing a seemingly perfect camber on my brand new plane iron, to dismay at having ruined a butcher block surface I was trying to smooth. Using the Lie-Nielsen 4-1/2 on a birch laminate slab from IKEA, I have grain tearout that exceeds anything my power planer and jointer have ever caused.
That I am a rank beginner at hand planing has been brought home in swift order. I wish I knew what I did wrong.
Another poster on this site warned me against planing that piece, which is made up of foot-long 1x1s (roughly), finger jointed on end and laminated to make up the 2-foot width. Some of the tearout happened downstroke of finger joints, so that may explain some if it. But there was tearout just as deep in the middle of pieces of the slab, notably in those with quartersawn flake showing. However, there really isn’t any pattern; some figured sections are smooth as glass and some apparently straight-grained ones have tearout.
I found that I got a lot of small chips stuck in the mouth of the plane while I was working. I brushed those away for a while. After a few minutes I set the chipbreaker back to about 1/16″ from the edge (from much closer), and saw some improvement. I did not flatten the chipbreaker prior to using the new plane, but now I think I’ll take a close look at that mating edge.
I’m now questioning not just my technique (undoubtedly needs help) but also my choice of this material as a workbench top. I’m going to want to flatten it periodically and I thought hand planing was the way to do that. And aren’t most good benchtops made from laminated hardwood?
It’s a good thing the surface I was planing is intended for the inside of a face-joined sandwich I am planning to make, to build up to 2-1/4″ thickness for the benchtop. But I’ll need to resolve this problem before proceeding with this project.
Any thoughts from you veteran hand planers?
Replies
Butcher block to me means laminated boards with the end grain facing up to make the face of the table or bench. But from your description, this sounds like something else - small pieces laminated, but the long grain portions are facing up? If so, your problem is likely that many (if not most) boards plane well in one direction and tear out or otherwise plane poorly when planed in the opposite direction. Unless the person gluing up the laminate oriented all the boards for optimal planing in one direction, you are inevitably planing some boards against the grain and thus, getting tear out. You can fight this some by planing perpendicular to the grain - i.e. across it. It can also help to take much less aggressive cuts - i.e., as thin a shaving as possible. Also, a 4 1/2 (typically a super smoother) isn't exactly the optimal plane for flattening a work bench, but each to their own.
Points well taken. There is no end grain showing on the top, but there are both flatsawn and quartersawn surfaces. In any case, as a surface, it's a pretty complex grain challenge, more than I appreciated at first.
I only have the 4-1/2, although I understand that a longer jointer would be better for flattening. The only reason I'm planing it is to remove the oil put on at the factory because I want to face-join two slabs, and am concerned about glue adhesion. I may just use G-2 epoxy and forget about the oil.
Still, I'm going to need a way to reflatten the bench over time. I'll try planing perpendicular and see what happens. If I have to do that, though, I won't want a jointer plane because the bench is going to be hinged to the wall and I won't have the space to push it across.
If you are face-laminating two large slabs, tear out on the gluing faces is largely irrelevant, as those faces will be hidden and there will be plenty of gluing surface for excellent adhesion even with significant tear out.
You keep saying that you will "need" to reflatten he bench from time to time. Maybe and maybe not, depending upon how stable those glue ups end up being - the relative humidity swings in the top's environment - and how well supported the top is. Scrapers and belt sanders might also be brought to bear.
Edited 4/23/2008 5:25 pm ET by Samson
Samson,
If I'm lucky I won't need to reflatten much at all. I live in California and we don't get wide humidity swings. I do expect that I will need to flatten it once I get it glued up and into position against the wall and on its legs.
Who knew this would be so complicated?
"Who knew this would be so complicated?"
It sounds like that other poster you referenced in post #1 did.
Matt,
You're right. I might just listen better from now on.
A top glued up from many small pieces, like your IKEA top, is inherently stable and will never need flattening.
The first response clearly explained why you are having problems. The hand tool approach to dealing with a piece with a lot of reversing grain is to use a scraper, either a simple card type or for large areas a scraper plane.
I noticed that you said you cambered the blade, meaning that you created a broad curve on the cutting edge. That isn't what you would use for final cleaning up an already flat surface.
John White
P.S. Epoxy isn't a solution for gluing oily surfaces.
Edited 4/23/2008 5:16 pm ET by JohnWW
John,
I don't have a scraper or scraper plane. The only reason I'm taking wood off the surface is to try to remove some of the oil that came with the slabs, so that I can glue them together. I could always try a sander, but all i have there is a random orbital, and I assumed that would put small valleys in the surface.
If regular glue won't adhere, and you say epoxy isn't the answer, is there any adhesive that would do this?
I thought buying two ready-made slabs would make for a simple procedure. Oh well.
For some reason which I don't recall, I had to put a polyurethane finish on top of the Ikea top I was working with. I wiped it down with lacquer thinner first then applied my finish.
Are you planing the top to flatten it or to remove the top oiled surface? I'd recommend a card scraper ($5) if you only need to remove the top surface, though this won't eliminate the oil which will have penetrated the block.Chris @ http://www.flairwoodwork.spaces.live.com
- Success is not the key to happines. Happiness is the key to success. If you love what you are doing, you will be successful. - Albert Schweitzer
Chris, there's the rub. Who knows how much wood I'd need to take off before the oil would cease to be a gluing concern? Planing seemed cleaner (for gluing) than sanding, and then there's scraping as well.
Instead of all that, I read something yesterday about using a solvent (acetone, mineral spirits) to lower the concentration of oils near the surface just long enough to do the glue-up. The thought was that the oil from below the surface would leech back toward the surface after a while, but the cleaning would last long enough for the glue to sink in before curing.
All of this may be a tempest in a teapot, though. I have a twelve-square-foot gluing surface, so even spot adhesion may be sufficient to keep the slabs together. I could be overkilling it; I tend to do that.
b,
Let me present another part/question that might help you to a conclusion.
Are you planning on adding an apron around the entire top (I'm assuming the answer is yes)? If so then mebbe the apron might offer another option for you in your quest for flat surface(s).
Taking on 2 relatively large slabs on your embarkation down the slippery slope is quite an ambitious undertaking to say the least.
Regards,Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Bob,
I was hoping the beef of the 2-1/4" sandwich would preclude my having to use an apron. My Record-type vise only needs that much cross section to bolt on. So I wasn't planning to use an apron.
You're right. This is no drawer front I've set out to tame.
I'm starting to think that I'll just random-orbit sand the two inner surfaces, wipe them down with mineral spirits, quickly air-dry, and apply the glue, and screw the slabs together while they set, clamping around the edges.
So I wasn't planning to use an apron.
Ya wanna bet!?
Sorry, couldn't resist. But before you dismiss the apron there are a lot of very good reasons why one is useful.
It will provide you with a continuous surface for registration whilst planing long boards and a real nice rear vise jaw at the same time. Covers up the edges of the two slabs and gives the bench a hefty look.
I would also venture a guess that someday you will be looking at your top and think, "Man I wish I had an apron".
Regards,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Edited 4/24/2008 3:37 pm ET by KiddervilleAcres
On the other hand, some, like myself, don't like aprons because they prevent you from easily clamping materials to your bench.
"On the other hand, some, like myself, don't like aprons because they prevent you from easily clamping materials to your bench."
There is that. I'm in that camp.
You've proved yourself credible to this point, so I've no reason to doubt you. I was planning to rip and cross about 1/4" off the edges to make them flush along their 2-1/4" thickness. I suppose I could always add an apron later. On the ends I don't see much point. I'm using a Record type vise, and its jaws are cast iron that I'll cover with wood; they don't lend themselves to using an apron unless I mortise into the top to do it. Seems unuseful. Although the vise isn't a traditional tail or end vise, it has a dog and that seems to justify its use on the end. I've thought if I were to add a front vise it might be the same kind, and that will mount easily without an apron.
I've seen front aprons that had rows of holes for horizontal dogs, but I don't know how handy those are.
So I guess I just haven't come across an application for the apron -- yet. But I'll be on the lookout and it should be easy enough to add later.
b,
That's cool as to the apron, your call.
they don't lend themselves to using an apron unless I mortise into the top to do it.
I'm a bit confused as to why you would need to mortise into the top to mount your vise? I don't recall seeing a vice that requires mortising into the benchtop but that doesn't mean there aren't such thangs. Mine (Lee Valley large front vice) mounts to the underside of my bench with no mortises required, at least that's how it is mounted. I did however mortise two round holes thru the apron for the vise screws to extend out to the front face of the vise.
Because I have an 8/4 apron I do lose 2" of throat capacity but in reality it isn't that much as one would want to line the rear jaw anyway, probably more like 1" loss. As to the row of dog holes in the apron, Lataxe devised a great mechanism/fixture to overcome this and utilise the dog holes on top of the bench; a very clever design which I am copying. Pssssst don't tell him as I'm not sure if he patented it or not. :-)
When I first built my workbench I faced a situation similar to yours in that I had 2 top surfaces that I wanted to connect together on their faces. I had a workbench with 2 ¾" sheets of plywood laminated together upon which I placed a solid core door ($25-used) to be my benchtop, yielding a 3¾" thick top. I affixed the apron on 3 sides (front & 2 ends) to the top(s) with plugged screws thru the apron into the top(s).
The apron, with 3 lag bolts in the rear holds the top(s) in place along with 3 lag bolts thru the backside into wall studs makes for a sturdy workbench even under heavy planing. Which brings me to another point - be careful about placement of bolts/screws in benchtops if you anticipate installing dogholes!
The long and short of it all to me is that workbenches can and often do get built for the user in support of their personal preferences, i.e. one size does not fit all!
It's all fun, right.
Regards,
P.S. I meant to tell you, the the B52s were one of my all time favorite bands.Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Bob,
The vise is a Record style (Taiwan knockoff but sturdy cast iron and good thick screw and bars). The back jaw is a 3/4" thick L section; the horizontal part of the L bolts under the benchtop and the vertical part forms the jaw itself. If I wanted to use a bench apron as the jaw liner, I'd need to fit the vertical part of the vise behind the apron. Since the apron would be flush to the benchtop, I'd need to cut an opening into the top to fit the vise's vertical jaw section. Whereas, if I just mount the vise outside the benchtop, its metal jaw will be exposed (no apron) and I'll simply use a wood liner. One tradeoff is that the liner, and thus the holding surface, would not extend the length of the bench, but I'm thinking of making a cleat of the same protruding thickness as the jaw/liner, and devising some clever way to hold it up against the bench front when working a long board.
Guess what: that's an argument in favor of an apron! Well, we'll see what invention necessity mothers for me. (Oblique reference to one of my favorite 60s bands.)
Now I'm intrigued about Lataxe's design. Maybe he'll leak his secret here.
You're so right about 31 flavors of workbench. As long as it's flat and strong and doesn't move, and can hold the vises, and hold work in place, and can be resurfaced if dinged up, it's a workbench. ...until I bump into another important wish-I-had characteristic through experience.
All the best from the Love Shack.
b,
One tradeoff is that the liner, and thus the holding surface, would not extend the length of the bench,
And therein is the rub.
I know it sounds like I'm lobbying for an apron but the reality of it all is that I haven't seen any disadvantages with respect to clamping wood to it. If you plan to edge plane boards fairly often then..............
Either way you're gonna lose some amount of throat capacity in the vise with wooden lined jaws.
Far Out Man,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Edited 4/25/2008 3:33 pm ET by KiddervilleAcres
Why didn't I think of this before: I could mount the vise and add an apron around the vise. Probably that's what you meant in the first place. That would give the bench the wider front edge and a lower lip to clamp to, and no need for a Rube Goldberg cleat that would clutter up the shop between uses.
OK, I've broken down. I'll use an apron the thickness of the jaw plus a reasonable liner, and mortise out the apron to fit the jaw.
b,
:-)
Sometimes the path down the slope is not straight.
Keep the Party IN Bounds,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Edited 4/26/2008 7:32 am ET by KiddervilleAcres
B52 , Just a suggestion pertaining to the laminating of the two slabs.
If you have a dado blade set, you can make some alignment grooves on the two mating surfaces, and glue in some splines, long grain to long grain, when you laminate the two halves.
This might help with the adhesion issue, as you would get down to some fresh wood.
Grooves could be 3/4 x3/4. Just my two cents.
A fine idea, one that would address both glue surface and alignment. Someone else suggested dowels, which sounds much easier, although it would only realy address alignment unless I use a lot of them.
Thanks for the thought. This is a great forum.
B52,
I'm wondering why you're even thinking of gluing these two slabs together in the first place. I can appreciate that you'd like a thick, heavy workbench top. But why glue it up?
Why not just screw them together from the underside in a few places? That will create the solid, heavy top you're after. And, after a few years of hacking up the top surface, you can unscrew the thing and maybe use one of the other sides.
I hardly ever use glue on any jigs or fixtures or workbenches in my shop. As a result I'm forever taking things apart and reusing this and that for another project. Some of the lumber and plywood in my jigs have so many screwholes from previous incarnations in other uses that it looks like they've been hit with a blast from a shotgun. I don't like to give up on good material just because it's got a few holes in it...
If you'd like to "index" the slabs in order to prevent the remote possibility of them shifting, you could either throw a few dowels into them, or, as another poster mentioned, dado both pieces and lay in some strips that fit the dados tightly - screwed, not glued!
Zolton If you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
Zolton,
I was coming at glue from a perpsective of not using hardware fasteners, but that probably makes more sense when I have control over the quality of the joint's mating surface.
In the end, I think you may have it. Enough screws will ensure the thing is solid with no meaningful gaps. This surface finish is giving me such a headache that I think you have hit upon the most sensible course.
"I read something yesterday about using a solvent (acetone, mineral spirits) to lower the concentration of oils near the surface just long enough to do the glue-up."
There's oil, and then there's oil. If the slab were oiled with a non-drying oil (e.g., mineral oil), then washing with solvent might help. But evidence that it really does help is lacking.
If the slab were oiled with a drying oil (e.g., linseed oil), then solvent won't do a thing. You have to remove enough wood to get to a reasonably clean substrate.
-Steve
The product is intended for kitchen counters, so I assume it's an edible oil, but I can't be sure.
Well, the problem is that there are both drying and non-drying oils that are edible. ;-)
-Steve
Certainly makes sense Steve.
When I edge glue cocobolo , oily wood, I pre-wipe the edges to be glued with Acetone. It dissipates the oil long enough for the water based glue to bond.
That is why I suggested the splines in dado grooves, In order to get down to some fresh wood . The other choice for gluing is epoxy, as I think someone posted. I'm not that crazy about using epoxy over broad surface. I don't know enough about it.
Edited 4/24/2008 7:17 pm ET by gofigure57
There were some results published several years ago--I don't remember exactly where, but it was discussed in this forum within the last couple of months--that came to the conclusion that when it comes to gluing oily woods, freshly planed or sanded surfaces do as well as ones cleaned with acetone or other solvent. The study wasn't comprehensive, as they didn't try every species with every kind of glue, so there's still more to learn.
I do think splines would afford the greatest potential for successful glue-up, but I can imagine that it might be difficult to achieve sufficient alignment to prevent the assembly process from turning into a nightmare. Maybe an array of biscuits instead? Since they're compressed, there's a little more leeway as far as alignment.
-Steve
B,
With laminated strips of wood you will have a more stable top but also grain going in many different diretions, one piece to the next. In many instances the grain will be rising in one bit but dipping in then other, relative to the direction you are planing across the top.
With a standard cutting angle of 45 degrees, rising grain is generally torn out. Te blade edge digs under the fibres and rips them up. It helps to increase the cutting angle to 50 or even 60 degrees (eg via them back bevels we were discussing) as this gives more of a sraping action - the chip breaks before the blade edge digs under it.
To understand grain direction and how to recognise/deal with it, search the Taunton site using the keyword "grain" in the Techniques section. There are several very good article that will tell you a lot about the subject, including how best to pane or otherwise flatten surfaces with difficult grain.
Lataxe
Lataxe,
Believe me, I've thought about that back bevel quite a bit during this little exercise. I did follow one of the suggestions and went over the section again at right angles to the laminations. No tearout, and I got funny little shavings. I don't know how to describe them but they weren't fine slices but rather like minute toothpick-shaped bundles. I suppose there were the annual rings coming off one after another and stacking up.
This is working out to be a lot of rigmarole just to glue two slabs together. I have half a mind (I guess I've proven that already) to just glue them up and see what happens. I could always throw them out if they don't stick.
B,
Samson is right about needing only enough contact to get stick-ability on the glue-together sides. I wouldn't worry about tear out on these surfaces; just get them reasonably flat. An RO sander can be used but it would take ages if there are significant bumps and dips; and (as you forsee) it is easy to intoduce dips that might interfere with the gluing-up.
When you plane across the grain, there is less chance of the blade trying to follow the grain if it's direction dips down into the wood. You get a rougher surface but less-deep tear out. Funnily enogh a shallow angle blade (eg 37 degrees) such as that in a shoulder plane used to trim tenons, works best at right angles to the grain.
That across-the-grain planing should still allow you to flatten the boards.
Once you've selected your top surface, try the high angle (back bevelled) blade in the conventional manner, with a very light cut and tight-closed mouth. This should get you a smoother surface even if there is a little tear out here and there. Scrape that away; or sand the whole top lightly as the final step (you already have "flat" and 99% smooth by then).
The virtue of your laminated boards, especially in the climate you describe, is that they are likely to be very stable once fettled and you won't need any significant re-flattening in the future.
Incidentally, for gluing the two halves together, consider screwing them from below (bottom piece has pilot hole equal to screw-shank diameter). The screws act as clamps across the whole area, if you put enough in. Plan to avoid the points where your dog holes and such will go.
Once the glue has cured you can remove the screws - or leave them if they won't interfere with further additions to your bench such as them dogholes, vise mountings and so forth.
Lataxe,
You are thoughtful and helpful. I really appreciate the care you've taken with my little situation. You've anticipated several of the other considerations I've had as well. In particular, the idea of temporary screws from below seems like an elegant way to eliminate gaps in case the slabs are warped at all.
I suppose the only remaining concern I have is whether the glue will adhere to the surface, which is either lightly oiled or waxed. Do you know of a way I could check that without sacrificing the pieces? How about if I drop a dollop of glue on it and let it dry? Would I be able to predict how it will hold in use by the way the sample dollop scrapes off?
Many thanks
B,
Chris is right, I think, that you should be able to just scrape off oil or wax. Although oil is said to "penetrate" it actually doesn't go in more than a fraction of a millimetre; and wax sits on the surface. There are chemical strippers that will remove oil or wax but you may still leave a residue and it isn't clear whether the stripper itself leaves some anti-gluing stuff behind.
Any significant oil or wax will stop most glues doing their binding thang with the conjoined wood fibres, so you do need to get the oil/wax surface treatment off the wood. One plane stroke usually does it though. However .... was that slab you bought pressure-treated with oil or some other anti-wetting agent? If so, you may have to plane more than that first shaving to get to "dry" wood, as the pressure may have forced the the stuff a little deeper. (Hopefully not).
Lataxe
Pressure treated? My gosh, I have no idea.
I believe what you are saying about oil penetration but that hasn't been my experience. I watco-ed my beech german bench. I've planed it several times over the years and always smell the watco. I think these "drying" oils actually stay wet in the wood. I've soaked tool handles in linseed oil and I think that went pretty deep. I think the depth of penetration has a lot to do with the grain orientation of the wood. You may not get much penetration in long grain fibers, but where end grain is exposed....Adam
Lataxe,
I hate to disagree with someone who agrees with me, but I do disagree with your statement of how "Although oil is said to "penetrate" it actually doesn't go in more than a fraction of a millimetre". It really depends on how much oil is applied and how it is applied. I sometimes drop my tool handles into a half-inch or so of oil overnight and let it wick up through the wood.Chris @ http://www.flairwoodwork.spaces.live.com
- Success is not the key to happines. Happiness is the key to success. If you love what you are doing, you will be successful. - Albert Schweitzer
Chris & Adam,
You're certainly correct that if wood is soaked in oil, it will take more up than just brushing or otherwise rubbing it on to the surface would impart - especially via the end grain or any other area of the wood with the cells of the grain cut.
My own experience in reclaiming old furniture that has been oiled/waxed is that "normal" surface costs don't penetrate much beyond what appears to be the top layer or three of cells (except where there is that end grain involved). On the other hand, some of the more volatile wood preservers do seem to get right into the cells, perhaps via some process where they replace the water in the cells.
I have a friend in the village who is a carpenter and always on the look out for free wood (like me). Someone tried to sell him a 10 foot oak pilling of 1 ft X 1 ft square section, out of the local dock that was being rebuilt. This piling had been there since the year dot and was periodically soaked in creosote when the tide was out, to keep out the rot and sea creatures that clag-on to wooden dock parts.
My friend had the great chunk in his garage and was planing off the surface with his electric hand plane "to get down to the wood". He had already taken off an inch all round. He was very very tired, up to his knees in shavings and the garage smelled like it was about to explode with creosote fumes, despite the wide-open doors and rooflights.
Phil the carpenter totally lacks any sense of smell, unfortunately; he could have easily passed-out if he hadn't had the doors and windows open because of the good weather. He never did reach the unaffected wood. Years and years of resoaking had seen the volatile oils in the creosote penetrate right through this very thick chunk of oak.
***
But B52 should be able to see (and smell) if there is any significant penetration when he planes off a surface of his slabs. It would be interesting to know what he finds. I suspect that, if there was no pressure treatment, the penetration will be minimal. If not (and perhaps anyway) it might be a better strategy to just screw those slabs together without glue, as mentioned in a previous post. Call it spot-welding of wood. :-)
Lataxe
Lataxe,
I can still smell what I believe to be the oil scent in the section I planed, but it seems weaker. When I scratch the surface with a fingernail, it doesn't get quite as waxy as the unplaned sections. I didn't hear your opinion of the glue dollop test, but that's giong to be my next step. I'll try to see if there is a difference scraping up the dried dollop in small planed and unplaned spots, and try to discern from that whether I should expect good adherence.
I'm rapidly progressing to the idea of an array of screws through the bottom and devil be damned with the adhesive.
I find it hard to believe that your plane is sharp and adjusted properly. A lot of problems one encounters with a plane can be fixed by sharpening its iron. So I recommend a three step approach:
1) Sharpen your iron to a mirror polish. Test it by pushing it, edge on, into a piece of printer paper. If it cuts the paper without a needing a slicing motion, you're in the right ball park. A strop will get it better though.
2) Shellac the butcher block. The shellac will help support some of the fibers and allow you to plane them. You can use Zinnser's Bull's eye shellac which should be available at your local hardware store. Doesn't matter which color you get.
3) Plane 90 degrees to the long grain. The resulting surface won't look as nice as long grain strokes. But this is only way to fix what you've done. Once you've gotten back to flat, scrape it with a card scraper. If you haven't got one, go buy or make one and a burnisher to go with it. Ever woodworker needs one of these and needs to know how to sharpen it.
Lastly, I know that material you are working with and I'm pretty sure its beech not birch. Watch out for the darker material. My experience tells me the darker stuff is curlier and softer and more prone to tearing out. I get the impression that it is the sapwood (anyone know off hand?) Whatever it is, its different from the lighter stuff. I have a work bench made of laminated beech and I have exactly the same problem planing it.
Adam
Adam,
Now that I've run the plane over the slab a few hundred strokes, I was planning to rehone and repolish anyway, so I'll try your paper test before and after that process.
Shellacing sounds like a nightmare to me since my whole purpose is to prepare the surface to accept glue for a face joining. I'll consider this, though, if this project goes on as long as the Democratic nomination race.
You were right about the 90 degree tip. It was counterintuitive to me but the strokes were much more benign, easing up only mini toothpicks of growth rings instead of the curly shavings I thought you were supposed to want from hand planing. But no tearout.
Re: the scraper. I ventured into my first hand plane on this project and the thought of mastering the scraper's grinding and burnishing was a second uncontrolled variable that I just hoped I could ignore for a while. You may be right that I need to bite the bullet. After all, I'm assembling this bench to build a craftsman bookcase and all of this surface preparation is dress rehearsal for working on cherry panels. I've seen dedicated scraper holders, and, of course, scraper planes. Do you think these are crutches or do they make the scraper easier and more reliable to use?
I looked again at the product. It is called PRONOMEN, and you are correct, it is beech. In fact, the product description is "oil, solid beech." (Thanks a lot, IKEA, I know all about the oil!) Not like I know or anything, but judging from the look of the growth-ring shavings, it does seem rather soft. The shavings look like bundles of 1" straw with very little material between the needles.
Many thanks for your kind thoughts, ideas, and help.
I think IKEA uses some form of vegetable oil, which could be linseed, but I don't think so. I was recommending the shellac only for the purpose of reducing tearout, but it will also act as a barrier that will allow you to glue to the oiled face. In the case of PVA, it may actually improve the bond.Regarding the scraper, recommend just procuring a piece of scrap saw blade. If you don't have one, contact me privately and I'll get you one or 5.Adam
Adam,
It is hard for me to imagine shellac, over oil or not, improving a glue bond. In fact, that suggestion might be the most wrong headed one I've read in quite a while. Do you, as a matter of course, shellac your mortises and tenons, and panel edges, before gluing them? Just wondering.
Ray
Ray
Ray,I'm thinking that if you have an oily wood, you need to suppress that oil somehow. Franklin recommends an acetone wipe for oily hardwoods. Here we have a much more oily surface. Shellac will stick to that surface and the PVA will stick to the shellac. So yeah, I think shellac will improve this glue joint. Makes sense to me. But I have no data. The only way to know for sure would be to run tests. Keep in mind, my recommendation is to shellac to reduce tear out. I'm assuming most of the shellac will get planned away. What little is left should help not hurt.Otherwise I'm not sure why you're saying what you're saying. We are talking about PVA and not hide glue. I only use hide glue in M&T joints because M&T's are unclampable. PVA develops very little bond strength in unclamped joints. Hide glue will develop bond strength across a gap and in fact prefers a small gap. Hot hide glue extrudes out of very tight joints (like epoxy).Your bad experience gluing old shellaced surfaces (I'm guessing here) may have been caused by the waxes and other stuff on top of the shellac effecting the joint, not the shellac itself. Don't know.Adam
Adam,
Can you expound abit on your statement "M-T joints are unclampable"? If my frame for a cabinet door is M-T jointed, I always clamp them after glueing and assembling. Don't know how else to get it to stay put til the glue dries.
Thanks,
Neil
I think he is referring to the fact that you can't really clamp the cheeks, since the width of the mortise is whatever it is--you can't clamp the cheeks any tighter than they are without distorting the workpiece.
-Steve
Steve's right.M&T, like dovetails are difficult to clamp. The surface that will best react load in both joints is the cross grain long grain to long grain surface. Chances are you're not clamping that surface. In both cases, it would be difficult to do so for even if you attempt it, you probably won't develop pressure where you want it.What people clamp is the end grain to long grain surface. This surface is structurally disadvantaged because the glue is in flat-wise tension. The presence of end grain makes this surface even less effective. Most glues don't do well with end grain. So I do this too to bring my joints up tight. But its not helping the glue per se.What I've been recommending is choosing a glue system that's appropriate for your specific joint and its specific fit characteristics. So dovetails and mortise and tenons should get one kind of glue. If the joints are very tight, a different glue should be used.In my shop, I use hot hide glue for everything except long edge joints (like over 4' in length). I use PVA for these joints. I mix and use the hot hide glue differently based on the specific situations I encounter.AdamP.S. I contacted Franklin's engineering department after reading the bondline pressure requirements for Titebond 2 many years ago. I asked for properties of unclamped specimens. The answer was that they've never done tests of that but didn't feel any properties would result. I think that's wrong. I think there are properties and obviously enough strength and stiffness to hold stuff for years and years. In my opinion, this would be a good next article for the guy who wrote the last glue article (which I thought was great). Woodworkers need to know what happens in less than ideal situations. I think hide glue will win in all but the tightest of joints.
Edited 4/25/2008 12:27 pm ET by AdamCherubini
Capisco, grazie. Is hide glue from a bottle (Titebond) a satisfactory substitute for the stuff from the glue pot?
Neil
Prego.It depends on what you want to do. Let me just throw this out there and you and I can trawl for a chemist:Hide glue is an organic compound with really long molecules. Its gram strength is an indication of its molecular weight. These long strands give the glue its strength. Over-heating the glue can cause it to "break down" physically, breaking the molecules into shorter (weaker) pieces.These long molecules also readily cross link providing stiffness. Adding salt of any sort reduces cross linking by bonding to the linkable elements. My experience tells me as glue is heated and reheated, it also looses its cross linking ability.The stuff in the bottle is hot hide glue with enough salt added to make it liquid at room temperature. By its very nature, its significantly less stiff than new hot hide glue. You need stiffness to transfer stress across a gap. Hot hide glue's got it, bottled glue, PVA and polyurethane don't. Flexible glues aren't going to transfer load across a gap. In the FWW test, they measured strength but didn't really measure stiffness which would have been valuable (maybe next time - I think we woodworkers can only take so much engineering). What's nice about the bottled glue is its convenience. It grabs quicker than PVA, provides more work time than hot hide glue but otherwise, I don't get the advantage of it. Hot hide glue is stronger, stiffer, with higher grab, plus gap filling ability. One disadvantage of hot hide glue is that its so thick and jells so quickly that it can extrude out of tight fitting joints. Bottled glue makes an excellent additive for hot hide glue, allowing you to customize your glue for whatever situation you desire.Woodworkers centuries ago believed that roughened surfaces provided the strongest joints. Modern analysis has proven this incorrect. But their observation was correct. The rough surfaces prevented hot hide glue from extruding out and gave them a bond where a perfectly smooth, tight joint would not. I think the rough sawn surfaces acted like a cleverly designed scrim cloth, allowing for perfect alignment, some internal pressure, and yet room for the glue. Very clever when you think about it.Adam
Adam,
I've always used yellow PVA wood glue but recently have begun to consider using hide glue. To me, it seems like a nuisance to have to mix and heat up glue when it's needed. Maybe that's why I've never mixed shellac either. I like the quick set-up time, but from what I've heard, hot hide glue cures a little too quick for my liking. I think I'll give the bottled version a try.
From what you wrote, it sounds like as long as your joints are reasonably tight, bottled hide glue will work fine. But if your joints are sloppy(er), hot hide glue is the better choice. (No, I am not saying your work is sloppy.)
Out of curiousity, are the majority of your tenons of the tusk, draw-bored, through and wedged in endgrain, or "normal" blind variety?
Also, a question for all the hot hide glue users out there: do you normally glue-up in more stages than if you were to use PVA glue? For example, glue one corner and check for square and let it cure before gluing the next corner.
Chris @ http://www.flairwoodwork.spaces.live.com
- Success is not the key to happines. Happiness is the key to success. If you love what you are doing, you will be successful. - Albert Schweitzer
Edited 4/25/2008 10:53 pm by flairwoodworks
Chris,I think you can get away with spit and chewing gum. I think in most cases, our furniture doesn't see anywhere near the stress these glues are good for. But there are circumstances where I think you need to know which glue is good for a particular situation. Chairmaking is one of those circumstances. Or anything made for children.I'm not sure which would be better in a tight M&T, pva or liquid hide glue. I think I would guess PVA. If there's any where glue can hide, hot hide glue or epoxy would be best I would think.The majority of my tenons are probably pegged, many draw bored. But I see unpegged thru or blind or thru tenons alot too.I don't stage my glue-ups. But carcass joinery is sort of naturally staged. I make the carcass, glue it together, then make the next parts and glue those on etc.Adam
Adam,
M&T joints: my preference, because of the grain challenge you cite, is to cut the tenon with my dado set. The outer blades have a tiny raised point at the outer edge of the tooth bevel, that leaves a small ridge in the dado. Not ideal when you want a dead flat groove, but on a tenon I think this makes a fine glue reservoir, ideal for this type of joint. The rest of the glue-up's success is up to me making a tight fit.
Glue-ups with gaps, or unclamped glue-ups: that is undoubetedly what I will have with these slabs unless I caul the whole setup like a madman. I'm about 99% ready to go with a generous coat of glue, but then to use a screw array, aligned on a grid to miss the dog holes. No need to make convex cauls or worry about the sandwich sliding out of register during clamping. I'll lightly clamp around the edges just before tightening the screws. This way I'll have the belt and the suspenders, and if the piece comes apart while I'm alive, I'll buy drinks all around for you guys in the forum.
Adam,
You mean glue to the shellac? Will it adhere?
That's mighty kind of you. I'd be interested if you have such scraps. Let me know if you want to put them in the mail some time.
Thanks
Bob
This may sound like a dumb question but that doesn't stop me from asking. :>)
Are the two slabs that far out of being flat? Or not flat enough to to glue them together and then deal with flattening the whole thang as needed?
Regards,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Bob,
Greetings to New Hampshire. No, I don't think they are far at all from flat. My 48" straightedge shows only a little light, and it's the good kind - the bump is in the middle and a simple clamping scheme will produce more force around the edges.
I've been struggling with the planing, not so much to flatten them, as to prepare the oiled surface to accept ashesive.
b,
Here's some pics of Mr. Froes ingenious device: http://forums.taunton.com/fw-knots/messages?msg=33300.56
For cryin out loud don't let on where you got these!
:_)
Regards,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
B, I've arrived at this thread late and am too overwhelmed to read each and every post, but have a thought about how to surface such a board/top when you can't get it to a big belt sander. I would try using a sled and router with a planing bit.
Darn, I had a link for you, but the pictures are gone. Have you seen what I'm referring to in any mags or online? If not, I'll try and find another example.
fg,
I have seen such a sled, recently enough that I can visualize the setup.
However, the prospect of shaving off enough of the slab to reveal the oil-free wood beneath, in order to leave a glue-adherent surface, has become larger than the project itself, I think. Last night I squeezed out a quarter-sized drop of two types of glue, long-drying and regular aliphatic, onto planed and unplaned sections of the slab. They're drying around the edges. When they are completed cured, I'll scrape them off and see if I can tell anything about the usefulness with this work. If they look like they'll hold sufficiently, I'm going to go ahead with a screw array through the bottom of the slab sandwich and a generous layer of glue.
In fact, unless the glues virtually slide off the wood, I should be OK. After all, the holding power per suqre inch doesn't need to be much. I have over 1,700 square inches in this glue-up, so even a paltry quarter of a pound per square inch would give me a 400-pound joint. And that's without the screws.
Much ado about nothing, although as Bob said above, the shortest distance downhill is not always a straight line (or something like that).
Nice to hear you weigh in on this thread. I enjoyed reading about your new tablesaw last month.
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